/*
 * The MIT License
 *
 * Copyright (c) 2013, Magnus Sandberg
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package jenkins.advancedqueue.priority.strategy;

import edu.umd.cs.findbugs.annotations.CheckForNull;
import edu.umd.cs.findbugs.annotations.NonNull;
import hudson.Extension;
import hudson.model.Cause;
import hudson.model.Cause.UpstreamCause;
import hudson.model.Queue;
import java.util.List;
import jenkins.advancedqueue.Messages;
import jenkins.advancedqueue.PrioritySorterConfiguration;
import jenkins.advancedqueue.sorter.ItemInfo;
import jenkins.advancedqueue.sorter.StartedJobItemCache;
import org.kohsuke.stapler.DataBoundConstructor;

/**
 * @author Magnus Sandberg
 * @since 2.3
 */
public class UpstreamCauseStrategy extends AbstractDynamicPriorityStrategy {

    @Extension
    public static class BuildParameterStrategyDescriptor extends AbstractDynamicPriorityStrategyDescriptor {
        public BuildParameterStrategyDescriptor() {
            super(Messages.Job_triggered_by_a_upstream_build());
        }
    }
    ;

    @DataBoundConstructor
    public UpstreamCauseStrategy() {}

    @CheckForNull
    private UpstreamCause getUpstreamCause(@NonNull Queue.Item item) {
        List<Cause> causes = item.getCauses();
        for (Cause cause : causes) {
            if (cause.getClass() == UpstreamCause.class) {
                return (UpstreamCause) cause;
            }
        }
        return null;
    }

    public int getPriority(Queue.Item item) {
        UpstreamCause upstreamCause = getUpstreamCause(item);
        if (upstreamCause == null) {
            // Cannot determine
            return PrioritySorterConfiguration.get().getStrategy().getDefaultPriority();
        }

        String upstreamProject = upstreamCause.getUpstreamProject();
        int upstreamBuildId = upstreamCause.getUpstreamBuild();
        ItemInfo upstreamItem = StartedJobItemCache.get().getStartedItem(upstreamProject, upstreamBuildId);
        // Upstream Item being null should be very very rare
        if (upstreamItem != null) {
            return upstreamItem.getPriority();
        }
        return PrioritySorterConfiguration.get().getStrategy().getDefaultPriority();
    }

    @Override
    public boolean isApplicable(Queue.Item item) {
        return getUpstreamCause(item) != null;
    }
}
